The proposed study is designed to examine the relationship between maternal depression and child outcome in the context of a prospective, longitudinal cohort of 915 children born between 1981 and 1984 at the Mater Misericordiae Mother's Hospital in Queensland, Australia. Previously collected data are available from interviews with each mother conducted during pregnancy, three to four days after delivery, six months after delivery, and when her child was five years of age. Data are also available on the developmental and cognitive status of the child at age five as measured by direct physical examination and testing. Follow-up data will be collected from the Mater cohort through interviews with the mother, father and child, and from questionnaires given to the teacher when the child is 15 years of age. We will examine the following hypotheses concerning the relationship between maternal depression and child outcome: (1) Severity of maternal depressive episodes will predict level of offspring's social, behavioral and emotional functioning as well as offspring diagnostic outcomes at age 15; (2) Severity and chronicity of maternal depressive episodes will interact to predict to level of offspring social, behavioral and emotional functioning as well as offspring diagnostic outcomes at age 15; (3) Severe levels of maternal depression that occur during the offspring's very early childhood or during the offspring's adolescence will be related to elevations in specific types of behavioral problems at age 15; (4) Hypotheses 1 through 3 will be supported even when social demographic factors such as mother's marital status and family socioeconomic status are controlled; (5) Maternal personality disorder, paternal psychopathology, marital conflict, impaired parent-child relations, stressful life events, and child physical health problems will mediate the relationship between maternal depression and child outcome; and (6) High self esteem, superior cognitive abilities and consistent relationships with fathers (i.e., protective factors) will be related to positive outcomes for those children whose mothers are depressed.